Factors Associated with Infectious Pulmonary Tuberculosis among Hospitalized Community Acquired Pneumonia Patients in Nakhon Phanom Province

Abstract

This study involved both a cross‐sectional and a case‐control design and was conducted
to investigate the prevalence of infectious PTB and the factors associated with infectious
PTB among adult hospitalized community‐acquired pneumonia (CAP) patients in
Nakhon Phanom Province between January 1, 2009 and June 30, 2011. The presence of
infectious PTB was diagnosed when either sputum acid fast bacilli (AFB) or a sputum
culture were positive for M.tuberculosis. CAP data were collected using the active
pneumonia surveillance standard form, and 400 CAP patients were interviewed:
200 CAP patients with infectious PTB and 200 CAP patients without infectious PTB.
Univariate and multivariate analyses were performed using STATA version 10.0
with statistical significance set at p< 0.05. The results showed that among 10,501
adult hospitalized CAP patients there were 385 new cases of infectious PTB; 131
were sputum AFB positive and 254 were sputum culture positive. This represented
a prevalence rate of 36.66 cases per 1,000 CAP patients, which is 53 times higher
than the prevalence of infectious PTB in the general population. The infectious PTB
prevalence was higher in males than in females with 50.99 cases per 1,000 male
CAP patients, a gender ratio of 1.5. The mean ages for CAP patients with and without
infectious PTB were 51.2+16.5 years and 57.5+16.7 years, respectively, and the
proportions of males in these two groups were 72% and 56.0%, respectively. The
factors positively associated with infectious PTB among adult hospitalized CAP
patients by multivariate analysis were a history of close contact with TB patients
(ORadj=9.03; 95%CI=3.29-24.77), pulmonary cavitation (ORadj=4.71; 95%CI=1.56-
14.14), a history of alcohol consumption (ORadj=3.86; 95%CI=1.86-8.02), hemoptysis
(ORadj=3.61; 95%CI=1.12-11.67), the absence of wheezing breath sound
(ORadj=3.66; 95%CI=1.81‐7.41), an abnormal chest radiograph (ORadj=2.98;
95%CI=1.73-5.14), a productive cough (ORadj=2.53; 95%CI=1.46-4.38), a history of
renal disease (ORadj=0.18; 95%CI=0.05-0.64), primary school education only
(ORadj=0.33; 95%CI=0.15-0.71) and unemployment (ORadj= 0.17; 95%CI=0.08-0.38).
This study indicates that there is a high prevalence of infectious PTB in adult
hospitalized CAP patients. The findings suggest that all CAP patients presenting with
a productive cough, hemoptysis, pulmonary cavitations or a history of close contact
with TB patients should be screened for TB. The clinical screening for infectious
PTB among adult hospitalized CAP patients should be implemented for early
diagnosis, prompt treatment and TB prevention in the community.